Ford 7.3L Powerstroke Running Rough / Misfire

7.3 Powerstroke Misfire

7.3 Powerstroke Misfire

There are many reasons why your 7.3 Powerstroke diesel engine might be idling rough or misfiring. Common symptoms can range from a worn-out injector to a bad sensor to stiction in your injectors. Regardless of the specific cause, it’s vital to immediately diagnose and repair the problem to prevent damage to other engine components.

What Is Causing My 7.3 Powerstroke to Idle Rough?

A rough idle in your 7.3 Powerstroke can result from several issues. An engine that’s having idle problems might show multiple symptoms, including:

  •    Bouncing or shaking during idle
  •    Inconsistent or jumping RPMs
  •    Skipping and shaking sounds

Some potential causes of these problems might include: 

Cause: There’s stiction in your fuel injectors.

Solution: Use Stiction Eliminator in your engine to clean out all your injectors and restore compression. Use Diesel Extreme to clear the entire fuel system.


Cause: Your injectors have failed at the mechanical level.

Solution: If the problem persists, run diagnostics for electrical and more serious injector issues.

7.3 Powerstroke Rough Idle

Intermittent Rough Idle Issues in a 7.3 Powerstroke Engine

If your 7.3 Powerstroke is running rough intermittently, one of several factors could be the culprit. There’s a good chance that stiction is the problem if your engine runs rough when cold but operates smoothly when warm. Treating your injectors with Stiction Eliminator will remove the stiction gumming.

We also recommend using Diesel Extreme to clean out your truck’s entire fuel system. Diesel Extreme will clean your cylinders, fuel lines and tank while dispersing the moisture from the whole system.

Analysis of Constant Rough Idle

If your truck is running rough all of the time, addressing the issue may be more challenging. Severe stiction will cause a vehicle to sputter and spit continuously. In this case, the problem is treatable, just like any other stiction issue.

However, these symptoms can also indicate a broken injector beyond the point of our product cleaning it.

An electrical issue, such as a sensor failure, can produce the same effects as stiction. An ICP sensor can often be the specific source of the problem. You will need your scan tool to diagnose the exact cause correctly.

Addressing Misfires

What Is a Misfire?

A misfire typically starts as a nuisance, but if you don’t address the issues right away, it could result in your 7.3 Powerstroke not starting or stopping completely when you least expect it. One of the leading indicators of a misfiring engine is rough or uneven idle. 

The symptoms of an intermittent miss are sometimes challenging to diagnose. The fuel injection control module (FICM) can cause an intermittent misfire — it is common to see a misfire between 45 and 65 mph when an FICM fails. 

A scan tool can help with diagnosing the cause of a misfire. If the scan tool doesn’t show any codes, go to — specifically the section titled Can I test my FICM to ensure that it is the culprit? — and follow the instructions for self-diagnosing your FICM. If the FICM appears to be functioning correctly, it may be best to send your truck to a qualified professional for further evaluation.


Failing Injector STICTION ELIMINATOR Challenge
The contents of, such as text, graphics, images, and other material contained on the Diagnose Your Diesel section are for informational purposes only. Always seek the advice of your mechanic or other qualified professional with any questions you may have regarding your vehicle’s condition.